Under certain operating conditions aircraft are vulnerable to accumulation of ice on component surfaces. It is well known that such accumulation of ice can lead to disastrous results. A wide variety of systems have been developed for removing ice from aircraft during flight and can be placed into three general categories: thermal, chemical, and mechanical.
The mechanical category of deicing systems operate by distorting the airfoil surface of the aircraft to be deiced. Distortion of the airfoil surface causes cracking in the ice accumulated thereon, and subsequent dispersal of that ice into the air stream passing over the aircraft component. The principal commercial mechanical deicing system is commonly referred to as pneumatic deicing wherein a component (e.g. the leading edge of a wing) of an aircraft is covered with a plurality of expandable, generally tube-like structures inflatable by employing a pressurized fluid, typically air. Upon inflation, the tubular structures tend to expand substantially the leading edge profile of the wing or strut and cracked ice accumulating thereon for dispersal into the airstream passing over the aircraft component. Typically, such tube-like structures have been configured to extend substantially parallel to the leading edge of the aircraft component.
These types of pneumatic deicing systems are provided over a multiplicity of component surfaces representing different portions of the aircraft. Since these different portions need only be deiced periodically under icing conditions, it is more energy efficient to deice the components one at a time in a predetermined sequence, thereby necessitating only one fluid compressor and one fluid magazine. Prior pneumatic deicing systems utilized to accomplish this objective include a plurality of valves which are controlled by a central controller to open and close in the predetermined sequence. Under certain circumstances however, it is not prudent to provide a valve and controlling system for each deicer located on the different aircraft components. This is particularly true when the components to be deiced are extremely thin, such as is found in engine inlets or propellers or fans.